How to use it
The wheel starts with four items, “Item 1” to “Item 4”, each with a weight of 1. Type over the names, press “Add item” if you need more, and use the ✕ at the end of a row to delete one you don’t.
- Under “Items (2–30)”, give each row a name. If even one row has no name, the wheel won’t spin. When there are only 2 items, the ✕ is disabled.
- The number box next to the name is the weight. Leave them all at 1 for equal odds. Raise an item’s number and its slice gets wider and it wins that much more often.
- Click the color swatch at the start of a row to change that slice’s color. The text on the slice switches to black or white, whichever reads better against the background.
- Press “Spin the wheel”. The button changes to “Spinning…” and the wheel makes at least three full turns before it stops. The slice under the pointer at top center is the winner, and its name appears under “Winner”.
- To keep drawing without any item coming up twice, turn on “Remove the winner from the list automatically”.
Below the wheel there is also a list showing each item’s number, name and weight, like “1. Item 1 (1)”.
Weight input limits: Decimals are fine, 0 is not. A weight has to be between 0.1 and 999. Outside that range you see “Weight must be a number between 0.1 and 999.” and the spin button is disabled. To leave an item out of a round, don’t enter 0. Delete it with the ✕ on its row. The draw takes weights into account to three decimal places.
Weights and odds
An item’s chance of winning is its weight divided by the sum of all the weights, and it takes up the same share of the wheel.
| Item | Weight | Chance of winning | Slice angle |
|---|---|---|---|
| A | 1 | 25% | 90° |
| B | 1 | 25% | 90° |
| C | 2 | 50% | 180° |
What matters is the ratio between the weights. Entering 1, 1 and 2 gives the same result as 10, 10 and 20. To make an item come up less, give it a value below 1. Two items with weights of 0.5 and 1.5 have chances of 25% and 75%.
For a raffle where people hold different numbers of tickets, enter each person’s ticket count as the weight. Someone with 3 tickets gets a slice three times as wide as someone with 1.
When names don’t fit on the wheel
Text on a narrow slice would overlap, so what the wheel shows depends on the slice.
| Slice angle | Shown on the wheel |
|---|---|
| 16° or more | Name (names over 12 characters are cut short and end in …) |
| 5° to under 16° | Number only |
| Under 5° | Nothing |
With equal weights, names are shown for up to 22 items. From 23 items on, each slice is narrower than 16° and every slice switches to a number. A big difference in weights does it too. With two items weighted 1 and 24, the smaller one is 14.4° and shows only a number.
When any slice shows only a number, the note “Items with a narrow slice show only a number on the wheel.” appears. Look up which item a number belongs to in the list below the wheel. Only the label gets shorter. The odds are not affected.
When the winner is decided
The winner is chosen the moment you press “Spin the wheel”, before the wheel moves. Random numbers from the browser’s crypto.getRandomValues pick one item in proportion to the weights. The tool then works out how far to turn the wheel so the pointer stops on that slice. The spin speed and stopping point don’t decide anything, so you can’t change the result by timing your click.
The pointer is set to stop inside a slice, never right on the line between two, so there is no doubt about which slice won. The winning slice gets a thicker outline.
If “Reduce motion” is switched on in your device settings, the result appears right away without the spin. The draw itself works the same way.
Setups to try
- Presentation order: enter the names, turn on “Remove the winner from the list automatically” and keep spinning. The order they come up is the order they present.
- Choosing lunch: don’t delete what you ate yesterday. Lower its weight to 0.5 instead. It can still come up, but only half as often as each of the others.
- A prize draw with losing slices: make two items, “Win” and “No prize”, with weights of 1 and 9, and the chance of winning is 10%.
History and saving
“This session’s history” lists the winning names from newest at the top to oldest at the bottom and keeps only the last 20. From the 21st spin on, each spin drops the oldest entry. Only the name is recorded, not which spin it was or the time.
Items and history are not saved. Reloading the page puts the items back to “Item 1” to “Item 4” and empties the history. If you have entered a lot of items, keep the tab open until the draw is over, and take a screenshot of the history if you need a record.